Hi,
I've seen that Quaternion fitting is on the TODO list of the Geometry
module. Since we already have Umeyama
(http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=88573) in our
library and since we just switched to Eigen, I was thinking it might be
of interest to you.
I've added the Eigen'ified implementation as well as a small CMAKE style
unit test.
In case you have any comments, just let me know.
Cheers,
Hauke